The Cloister is a Green Room in Blue Prince (Room 66, Unusual rarity, gem cost 3, 4-way shape). On its own it looks like a dead-end decorative room, but it hides one of the cleanest allowance tricks in the game and, once upgraded, becomes one of the most flexible floorplans in the house. This guide covers the real mechanics from the Blue Prince wiki: how to open the sealed center, what the eight upgrade variants actually do, and which three are worth committing to.
For the broader room economy, the best rooms tier list ranks every floorplan, and the room drafting guide explains how 4-way rooms like the Cloister fit into a reliable draft.
The Cloister basics (real stats)
| Property | Value |
|---|---|
| Room number | 66 |
| Type | Green Room |
| Rarity | Unusual |
| Gem cost | 3 |
| Shape | 4-way |
| Drafting | Only in the center 21 tiles |
As a 4-way room it can only be drafted in the center 21 tiles of the house. It is also the default fallback when Green Rooms are being drafted by Secret Passage or Prism Key and nothing else is available, and it sits in the Center Prismatic Pool. Importantly, the central reservation can show up to four dig spots, but the area is sealed on all four sides — those dig spots cannot be interacted with normally.
How to open the hidden wall (Allowance Token)
The sealed garden is not decoration. A note in the Solarium teaches the method: while face-to-face with the angel, press the base of the two pillars on either side of you. Doing so opens the Cloister wall, revealing a hidden note and an Allowance Token on the pedestal behind the statue. That token is free allowance you can grab every time the room appears, which is why the Cloister is worth drafting even before you upgrade it.
Two interactions change how often you see it: activating The Southern Cross makes the Cloister more common that day, and Library-filtered gems interact with it like other Green Rooms (two gem flowers, Prism Passage defaults to slot 3).
The eight upgrade variants (real effects)
When you use an Upgrade Disk at a terminal, the Cloister is one of the selectable floorplans. There are eight possible upgrades, but only three are offered to choose from at any one upgrade. Every upgrade permanently changes the Cloister’s Dynamic Rarity to Standard. The eight, with their real triggered effects:
| Upgrade | What it does when rooms are drafted from it |
|---|---|
| Cloister of Rynna | Drafting a Green Room from it increases luck for all future rooms; two activations are roughly a global Veranda |
| Cloister of Joya | Drafting Kitchen / Pantry / Furnace permanently adds +5 steps to the Dining Room Main Course |
| Cloister of Dauja | Drafting listed rooms grants +2 stars |
| Cloister of Veia | Any fireplace room drafted spawns with 8 additional dirt piles |
| Cloister of Mila | Bedroom doors drafted from it contain one extra item |
| Cloister of Lydia | Drafting a Shop adds +2 gold to your allowance |
| Cloister of Orinda | Drafting a Blackprint opens a random Antechamber door |
| Cloister of Draxus | Sets gem cost to 0 (the only upgrade with a different gem cost); drafting a Dead End grants +4 dice |
Which three to pick
Ranked by how broadly they pay off, using the real effects above:
- Cloister of Rynna — Luck is the single most universal stat in Blue Prince; raising it for every future room is a quiet win on every draft. Two triggers approach a house-wide Veranda, which is why Rynna is the safest “always take” pick.
- Cloister of Draxus — Free to draft (gem cost 0) and it feeds you +4 dice on Dead Ends. Dice are the best reroll currency in the game, so a 0-cost room that prints them is a long-term economy engine.
- Cloister of Joya or Lydia — Joya compounds into the Dining Room (permanent +5 steps per trigger, excellent if you lean on the Dining Room), while Lydia just prints +2 gold allowance per Shop draft. Pick Joya if you use the Dining Room, Lydia if you draft many shops.
- Cloister of Dauja — +2 stars per trigger is strong for star-dependent builds, but more situational than the top three.
- Cloister of Mila / Veia / Orinda — Niche: extra Bedroom items, dirt piles, or Antechamber access are useful only for specific runs, so they fall to the bottom of a general ranking.
The practical advice: if Rynna and Draxus are among your three offered, take both without hesitation, then grab Joya or Lydia based on your usual route. The gem guide explains why a 0-gem Draxus matters more than it looks, and the coat check guide covers how permanent allowances like the Cloister token stack across days.
Cloister versus other Green Rooms
The Cloister looks worse than it is because its central garden is sealed and its dig spots are unreachable. Compared with other Green Rooms, its edge is consistency: it is the Prism Passage and Secret Passage fallback, so it appears even when your draw is empty, and its 4-way shape plugs center tiles that narrower rooms cannot. The real upside is the Allowance Token and the upgrade tree — no other single Green Room turns into both a luck engine (Rynna) and a 0-gem dice printer (Draxus). If you are optimizing rare-room odds, the room rarity guide shows where Unusual rooms like the Cloister sit in the weighting.
FAQ
Is the Cloister worth drafting if I am not upgrading it? Yes. The hidden Allowance Token behind the angel is free money every appearance, and The Southern Cross can make it show up often.
Do I need the Solarium note to open the wall? You need to know the method (press the pillar bases while facing the angel), and the Solarium is where that knowledge is found. Once you know it, any Cloister wall opens the same way.
Can I pick all eight upgrades? No. Only three are offered at each Upgrade Disk use, and you choose one of those three. You cannot stack all eight on a single floorplan.
Does the upgrade change the Cloister’s rarity? Yes — taking any Cloister upgrade permanently sets its Dynamic Rarity to Standard, which affects how often it appears in future drafts.